The present invention relates to a personnel monitoring system, and more particularly to a house arrest monitoring system wherein individuals who wear a special tag can be electronically monitored for compliance with a court-ordered sentence (or similar restriction) requiring them to remain at a specified location(s) at a specified time(s). Even more particularly, the present invention relates to such an electronic house arrest system wherein a monitoring officer, e.g., a probation or parole officer responsible for making periodic and/or random physical checks with the individuals being monitored at or near the specified monitoring location(s), can immediately and silently report to a central monitoring location that backup help or assistance is needed at such location.
Electronic house arrest monitoring (EHAM) systems are known in the art. Such systems fulfill a valuable need in that they allow a relatively large number of individuals who have been ordered by a court to remain under house arrest, or who are under parole or probation requirements to remain at certain locations at specified times, to be electronically monitored for compliance with whatever restrictions have been imposed. Such electronic monitoring can advantageously be carried out at a fraction of the cost of incarceration of the monitored individuals; and also at a much reduced cost over conventional probation/parole monitoring procedures. Further, an electronic monitoring system offers the advantage of reducing the physical contact between a monitoring officer, e.g., a probation or parole officer, and the monitored individual, which physical contact can, at certain times and certain locations, pose a potential danger to the officer.
One type of house arrest monitoring system known in the art, referred to as an "active" monitoring system, generates and transmits radio wave signals as part of the monitoring process. Such an active EHAM system is described, e.g., in U.S. Pat. No. 4,918,432, issued to Pauley et al. In the Pauley et al. active EHAM system, each individual being monitored is fitted with an electronic bracelet or anklet. Such bracelet or anklet, referred to in the referenced patent as a "tag", includes a transmitter that periodically transmits a identifying radio wave signal (unique to each tag, and hence to each individual) over a short range (e.g., 150 feet). A field monitoring device (FMD) is installed at each location where the monitored individual(s) is supposed to be. If the monitored individual(s) is present at the FMD location, a receiver circuit within the FMD receives the unique identifying signal. The FMD processing circuits can thus determine that a specific individual is present at the location of the FMD when the signal is received. This information (which may be considered as "presence data") is stored within the FMD memory circuits for subsequent downloading to a central monitoring location. A computer, or central processing unit (CPU), located at the central monitoring location periodically or randomly polls the various FMD locations through an established telecommunicative link, e.g., through standard telephone lines, in order to prepare reports indicating the presence or absence of the individuals at the specified locations. Such reports are then used by the agency charged with the responsibility for monitoring the individuals to ascertain whether or not such the monitored individuals are in compliance with whatever restrictions have been imposed.
An important feature of the Pauley et al. EHAM system is the ability of the tag to detect any attempts to tamper with it, e.g., to remove the tag from the monitored individual. If a tamper event is detected, such occurrence is immediately signaled to the FMD, and the FMD, in turn, includes the ability to immediately establish telecommunicative contact with the central CPU in order to report such tamper event. All data sent from the FMD to the central CPU includes address-identifying data that identifies the specific location where the FMD is located. The '432 Pauley et al. patent is incorporated herein by reference.
Other active EHAM systems known in the art also include the ability to detect tamper events, such as U.S. Pat. No. 4,777,477, issued to Watson, wherein any attempt to cut or break the strap that attaches the tag to the individual is detected and signaled to a local receiver. The '477 Watson patent is also incorporated herein by reference.
Still other active EHAM systems known in the art include the ability to adaptively change the monitoring configuration to best suit the needs of the agency responsible for carrying out the monitoring function. See U.S. Pat. No. 4,952,928 issued to Carroll et al., which patent is likewise incorporated herein by reference. The Carroll et al. system advantageously includes the ability to sense and monitor various physiological data of the monitored individual, such as heart rate, blood pressure, body position (horizontal or vertical), and the like, so that such data can be analyzed at the central monitoring location to determine if the monitored individual is complying with other restrictions, such as abstinence from drugs or alcohol.
Another type of electronic house arrest system known in the art is a "passive" monitoring system. A passive system typically does not involve the generation and transmission of radio wave signals, such as are used in the active EHAM systems. An example of a passive system is disclosed in U.S. Pat. No. 4,747,120, issued to Foley. In the Foley system, a central computer randomly establishes telephonic contact with a specific location whereat the monitored individual is supposed to be at a time when such individual is supposed to be there. The computer then instructs the individual, e.g., using synthetically generated speech, to perform some act, such as inserting a specially coded wristlet permanently affixed to the individual (and hence unique to the individual) into a decoding device interconnected with a telephone at the remote location. If the individual successfully completes the act, which act is designed to be something that only the correct individual can successfully do, then a verify signal is sent back to the central computer over the telephone lines and the computer thus determines that the correct individual is at the remote location. If the verify signal is not received, then the computer determines that the correct individual is not at the specified location.
Another type of passive EHAM system known in the art includes the ability to also test the monitored individual for compliance with other restrictions, in addition to staying at a specified location, such as abstinence from alcohol and drugs. See, e.g, U.S. Pat. No. 4,843,377, issued to Fuller et al. In such systems, a breathalyzer device is coupled to the telephone line. If the blood alcohol level of the monitored individual exceeds prescribed limits, then an appropriate signal indicating this fact is sent to the central monitoring location. One embodiment of the system disclosed in the Fuller et al. patent includes the use of a camera at the remote location. The picture of the monitored individual is converted to electronic data and transmitted to the central location, i.e., over the telephone lines, where it is reconstructed so that the image of the monitored individual can also be checked.
Regardless of the type of EHAM system employed, whether passive, active, or combinations of active and passive, there frequently arises a need for a monitoring officer, or other individual from the monitoring agency, to physically go to the monitoring location and verify that the monitored individual is in fact at the monitored location, and that other restrictions that may have been imposed are being complied with. At other times, visits must be made to the field to check out the operation of the monitoring equipment. When this need arises, the monitoring officer, in going to the monitored location, may place himself or herself in danger of bodily harm, either directly from the monitored individual (who may be drunk, or under the influence of drugs), or from other individuals in the same neighborhood as the monitored individual. What is needed, therefore, is an EHAM system that provides the monitoring officer some measure of security and protection as such field visits are made.
One technique known in the art for providing officer safety is to require that a team of officers, e.g, at least two officers, perform the actual visit to the monitoring location. The team of officers can then use established procedures commonly practiced by law enforcement agencies to assure the safety of the officers involved, including carrying firearms and other weapons. Unfortunately, many monitoring agencies do not have the budget nor the manpower to dispatch a team of officers to a specified location to follow up on compliance with mandated restrictions. Further, a team of officers may intimidate the monitored individual, particularly if they are carrying firearms, and prevent the free flow of information that the monitoring officer may need. Hence, what is needed is an EHAM system that does not require a team of monitoring officers to check up on compliance with mandated restrictions, and that facilitates a single officer making such visits. However, should a dangerous situation develop, there is also a need for an EHAM system that allows an appropriate team of law enforcement officers, e.g., police or sheriff officers from the closest station, to be immediately dispatched to the location where the dangerous situation exists.
Another technique used in the art to provide a measure of safety for the monitoring officer is to require the monitored individual to step outside, e.g., on the front porch or otherwise in front of the monitored location, so that the monitoring officer can readily see, and even talk with, the individual from the relative safety of his or her automobile. In this way, the officer can simply "drive by" the monitored location without having to physically enter the premises. One drive-by system even provides a means for issuing an electronic "callout" signal to the monitored individual, so that he or she knows the officer is outside, and that the monitored individual must thus step outside so that the monitored individual can be seen by the officer. See, e.g., U.S. Pat. No. 4,924,211, issued to Davies et al. Unfortunately, requiring the monitored individual to always step outside of his premises may preclude the monitoring officer from discovering some necessary information needed to properly ascertain if the individual is in full compliance with the mandated restrictions of the house arrest. Hence, what is needed is an EHAM system that allows the officer to enter the premises of the monitored individual, and still provides some measure of protection while there.